White House Looks to Persuade Senators to Hold Off on Sanctions

WASHINGTON—Under pressure over nuclear talks with Iran, top Obama administration officials planned to try Wednesday to quell any move by lawmakers to tighten sanctions while diplomacy is under way.

The absence of a quick agreement in Geneva last weekend has rekindled interest among some lawmakers for a new round of sanctions against Iran. The White House has counseled against that because of the delicate nature of the talks, which are...